It's not the guy who worries that homeless shelters are too comfortable (Ben Carson). Not the guy arguing to dismantle lesbian, gay, bisexual and transgender rights (Jeff Sessions). Not the mastermind of the Bowling Green Massacre (Kellyanne Conway).

To be sure, all these aides and bureaucrats are doing damage. They are degrading norms, enacting bad policy and putting our country and planet at grave risk.

But right now the "most dangerous" title belongs - aside from the tweeter in chief, of course - to someone in a much less sexy job, with a much less scandalous background.

It's Mick Mulvaney, director of the Office of Management and Budget.

In terms of both immensity and immediacy, the threat Mulvaney presents is far greater than any of the slow-motion train wrecks happening elsewhere in the administration. That's because he seems hell-bent on wreaking a global crisis within the next two months.

Not a century from now. Not a decade from now. In two months.

That's when the government will run out of money needed to pay bills Congress has already incurred, according to Treasury Secretary Steven Mnuchin, if Congress does not act to raise the debt limit.

What would follow? Just a constitutional, political and global financial crisis.

Arguably, the U.S. government would be in violation of the 14th Amendment ("The validity of the public debt of the United States . . . shall not be questioned"). The government's ability to continue paying Social Security checks, interest on the debt and other basic obligations would likewise be at risk.

Most important, this would irrevocably destroy the United States' sterling reputation as a borrower.

U.S. debt is considered the safest of safe assets, and as such, Treasury securities are the benchmark of the global financial system. Causing creditors to question whether they'll receive full and timely payments would trigger panic in markets throughout the world.

Technically, we already hit the debt ceiling in March. In the months since, Treasury has engaged in extraordinary accounting measures to avoid outright default. But come early fall, those measures will be exhausted. The United States will become a deadbeat.

The debt ceiling is a product of the misguided belief that limiting the official borrowing capacity of the government would force legislators into frugality. In reality, it has done nothing to curb financial profligacy. Its chief effect is to periodically offer some political faction - sometimes the minority party, sometimes the nuttier fringe of the majority party - the power to take a very valuable hostage.

Mnuchin has urged Congress to pass a debt-limit hike with no strings attached. The government would thereby dodge default with minimal drama and without spooking markets.

But Mulvaney has other plans.

During his six years in Congress, he voted against raising the debt limit four times. One might hope he was merely posturing, since he was able to cast such votes with the knowledge that his colleagues would ultimately pass the bills.

Unfortunately, as OMB director, Mulvaney has continued to be breathtakingly irresponsible with the creditworthiness of the United States.

In May, he publicly contradicted Mnuchin by arguing that a debt-ceiling increase should be coupled with divisive spending cuts, which would inevitably complicate an already politically fraught process.

And on Sunday, he told CNN's Jake Tapper that Congress must not pass any legislation - not even a debt-ceiling hike - until the notoriously impossible Obamacare repeal is done. President Trump echoed this thinking on Twitter as well.

So long as Mulvaney still has the president's ear, we're all living dangerously.